Combining different treatment strategies successively or simultaneously has become recommended to achieve high purification standards for the treated discharged water. The current work focused on combining electrocoagulation, ion-exchange, and ultrasonication treatment approaches for the simultaneous removal of copper, nickel, and zinc ions from water. The removal of the three studied ions was significantly enhanced by increasing the power density (4–10 mA/cm2) and NaCl salt concentration (0.5–1.5 g/L) at a natural solution pH. The simultaneous removal of these metal ions at 4 mA/cm2 and 1 g NaCl/L was highly improved by introducing 1 g/L of mordenite zeolite as an ion-exchanger. A remarkable removal of heavy metals was reported, as the initial concentration of each metal decreased from approximately 50 ppm to 1.19 for nickel, 3.06 for zinc, and less than 1 ppm for copper. In contrast, ultrasonication did not show any improvement in the treatment process. The extended Langmuir isotherm model convincingly described the experimental data; the Temkin and Dubinin-Radushkevich isotherm models have proven that the removal processes were physical and exothermic. Finally, the pseudo-second-order kinetics model appropriately explained the kinetics of the process with correlation coefficients of 0.9337 and 0.9016, respectively.
The kinetics of nickel removal from aqueous solutions using a bio-electrochemical reactor with a packed bed rotating cylinder cathode was investigated. The effects of applied voltage, initial nickel concentration, the rotation speed of the cathode, and pH on the reaction rate constant (k) were studied. The results showed that the cathodic deposition occurred under mass transfer control for all values of the applied voltage used in this research. Accordingly, the relationship between concentration and time can be represented by a first-order equation. The rate constant was found to be dependent on the applied voltage, initial nickel concentration, pH, and rotation speed. It was increased as the applied voltage increased and decreased as t
... Show MoreIn this paper, split-plate airlift electrochemical reactor as an apparatus with new configuration for wastewater treatment was provided. Two aluminum plates were fixed inside the reactor and present two functions; first it works as split plates for internal loop generation of the airlift system (the zone between the two plates acts as riser while the other two zones act as downcomer) and second it works as two electrodes for electrocoagulation process. Simulated wastewater contaminated with zinc ions was used to test the performance of this apparatus for zinc removal by studying the effect of different experimental variables such as initial concentration of zinc (50-800 ppm), electrical current density (2.67-21.4 mA/cm2), init
... Show MoreThermal and catalytic pyrolysis of waste plastics in an inert atmosphere has been regarded as a creative method, since pyrolysis can convert plastics waste into hydrocarbons that can be used either as fuels or as a source of chemicals.
Natural Iraqi kaolin clay was used to synthesis the NaX nano- zeolite by hydrothermal conditions with average particle size equal to 77.63nm.Thermal decomposition kinetics of high-density polyethylene (HDPE) in the absence and presence of catalysts nano NaX Zeolite was investigated. Thermal and catalytic degradation of HDPE was performed using a thermogravimetric analyzer in nitrogen atmosphere under non-isothermal conditions 4, 7 and 10 °C/min heating rates were employed in thermogravimetric anal
... Show MoreMany species are resistant to heavy metals in their surrounding polluted environment and Staphylococcus sp. is an example. This study aimed to isolate and characterize bacteria resistant to heavy metals in the Shatt Al-Arab River in southern Basra, Iraq. Based on the morphology and using Vitek II system, and due to their high resistance to heavy metals (mercury and chromium), two species of Staphylococcus (Staphylococcus lentus and Staphylococcus lugdunensis) were chosen and isolated. The minimum inhibitory concentration (MIC) of the isolates against Hg and Cr was determined after 72 h. of incubation in solid media. All isolates were resistant to Hg (2000 mgL-1) and Cr (4000mgL
... Show MoreAdsorption techniques are widely used to remove organics pollutants from waste water particularly, when using low cost adsorbent available in Iraq. Al-Khriet powder which was found in legs of Typha Domingensis is used as bio sorbent for removing phenolic compounds from aqueous solution. The influence of adsorbent dosage and contact time on removal percentage and adsorb ate amount of phenol and 4- nitro phenol onto Al-Khriet were studied. The highest adsorption capacity was for 4-nitrophenol 91.5% than for phenol 82% with 50 mg/L concentration, 0.5 gm. dosage of adsorbent and pH 6 under a batch condition. The experimental data were tested using different isotherm models. The results show that Freundlich model resulted in the best fit also
... Show MoreSoil is a crucial component of environment. Total soil analysis may give information about possible enrichment of the soil with heavy metals. Heavy metals, potentially contaminate soils, may have been dumped on the ground. chromium, nickel and cadmium,
In this paper, thirty six samples of canned vegetables were collected randomly from
different markets in Baghdad city from October 2013 till March 2014. The study
includes identifying the concentration of some heavy metals (lead, nickel, zinc and iron)
by flameless atomic absorption spectrophotometery. It was found that the higher
concentrations of heavy metals in canned vegetables, was lead 1.179 ppm in olive,
nickel 0.9078 ppm in olive, while zinc 10.143 ppm green peas and iron 90.601ppm in
white asparagus; but the lower concentrations represents with lead 0.0021 ppm in green
asparagus, nickel 0.0202 ppm in mushroom, while zinc 0.528 ppm in white asparagus
and iron 4.061 ppm in green peas. Canned food has been r
Coagulation - flocculation are basic chemical engineering method in the treatment of metal-bearing industrial wastewater because it removes colloidal particles, some soluble compounds and very fine solid suspensions initially present in the wastewater by destabilization and formation of flocs. This research was conducted to study the feasibility of using natural coagulant such as okra and mallow and chemical coagulant such as alum for removing Cu and increase the removal efficiency and reduce the turbidity of treated water. Fourier transform Infrared (FTIR) was carried out for okra and mallow before and after coagulant to determine their type of functional groups. Carbonyl and hydroxyl functional groups on the surface of
... Show MoreOrganic contaminants are used to be found in industrial wastewater treatment procedures, and heavy metal ion removal is difficult. Photo Fenton reaction activity was exploited in this study to decompose organic contaminants using a functional composite hydrogel. Polyacrylonitrile (PAN), Fe3O4 particles, and graphene oxide make up the hydrogel (GO). It is made from GO/ Fe3O4 and is made using the precipitation technique. GO is made from graphite using the Hummers process. And it has exceptional mechanical strength and Photo-Fenton activity as a result of various breakdown data that were influenced differently, such as H2O2 concentration, dye concentration, temper
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